Omecamtiv mecarbil (OM) is a positive cardiac inotrope in phase-3 clinical trials for treatment of heart failure. Although initially described as a direct myosin activator, subsequent studies are at odds with this description and do not explain OM-mediated increases in cardiac performance. Here we show, via single-molecule, biophysical experiments on cardiac myosin, that OM suppresses myosin's working stroke and prolongs actomyosin attachment 5-fold, which explains inhibitory actions of the drug observed in vitro. OM also causes the actin-detachment rate to become independent of both applied load and ATP concentration. Surprisingly, increased myocardial force output in the presence of OM can be explained by cooperative thin-filament activation by OM-inhibited myosin molecules. Selective suppression of myosin is an unanticipated route to muscle activation that may guide future development of therapeutic drugs.
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http://dx.doi.org/10.1038/s41467-018-06193-2 | DOI Listing |
Clin Transl Oncol
January 2025
Medical Oncology Department, Hospital del Mar, Parc de Salut Mar, Spanish Group for Breast Cancer Research (GEICAM), Barcelona, Spain.
Therapeutic decision-making for older patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer highlights the importance of a comprehensive geriatric assessment (CGA). This assessment considers the functional status, comorbidities, and relevant conditions of the patient, and allows for an estimation of life expectancy, but it does not facilitate individualized treatment plans. There are also other challenges to consider related to the cardiac toxicity of the treatments and the under-representation of older patients in clinical trials.
View Article and Find Full Text PDFJ Am Heart Assoc
January 2025
John P. Hussman Institute for Human Genomics, University of Miami Miami FL USA.
Background: Carotid intima-media thickness (IMT) is a measure of atherosclerosis and a predictor of vascular diseases. Traditional vascular risk factors and genetic variants do not completely explain the variation in carotid IMT. We sought to identify epigenetic factors that may contribute to the remaining carotid IMT variability.
View Article and Find Full Text PDFJ Contemp Dent Pract
September 2024
Department of Periodontology, Narsinhbhai Patel Dental College and Hospital, Sankalchand Patel University, Visnagar, Gujarat, India.
Aim: This study aims to evaluate the impact of platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) on pain, swelling, trismus, soft tissue healing and bone regeneration following mandibular third molar extraction.
Material And Methods: A systematic review was conducted from a period of January 2014 to June 2024 using PRISMA guidelines. The search strategy included databases such as Scopus, PubMed, Google Scholar, and Cochrane Central Register of Controlled Trials, using key terms related to "PRF", "PRP", oral surgery, and third molars.
Hum Brain Mapp
January 2025
Department of Psychology, Concordia University, Montreal, Quebec, Canada.
The cortex and cerebellum are densely connected through reciprocal input/output projections that form segregated circuits. These circuits are shown to differentially connect anterior lobules of the cerebellum to sensorimotor regions, and lobules Crus I and II to prefrontal regions. This differential connectivity pattern leads to the hypothesis that individual differences in structure should be related, especially for connected regions.
View Article and Find Full Text PDFJACC Adv
January 2025
Institute and Department of Endocrinology and Metabolism, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Objectives: The purpose of this study was to assess the associations of choline metabolites with incident HF and examine the effect modification by genetic susceptibility.
Methods: This prospective cohort study followed 245,072 participants from the UK Biobank from baseline (2006-2010) until March 30, 2023.
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